# Copyright (c) 2012 - 2015 EMC Corporation, Inc.
# All Rights Reserved.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.
"""iSCSI Drivers for EMC VNX array based on CLI."""

from oslo_log import log as logging

from cinder.volume import driver
from cinder.volume.drivers.emc import emc_vnx_cli

LOG = logging.getLogger(__name__)


class EMCCLIISCSIDriver(driver.ISCSIDriver):
    """EMC ISCSI Drivers for VNX using CLI.

    Version history:
        1.0.0 - Initial driver
        2.0.0 - Thick/thin provisioning, robust enhancement
        3.0.0 - Array-based Backend Support, FC Basic Support,
                Target Port Selection for MPIO,
                Initiator Auto Registration,
                Storage Group Auto Deletion,
                Multiple Authentication Type Support,
                Storage-Assisted Volume Migration,
                SP Toggle for HA
        3.0.1 - Security File Support
        4.0.0 - Advance LUN Features (Compression Support,
                Deduplication Support, FAST VP Support,
                FAST Cache Support), Storage-assisted Retype,
                External Volume Management, Read-only Volume,
                FC Auto Zoning
        4.1.0 - Consistency group support
        5.0.0 - Performance enhancement, LUN Number Threshold Support,
                Initiator Auto Deregistration,
                Force Deleting LUN in Storage Groups,
                robust enhancement
        5.1.0 - iSCSI multipath enhancement
        5.2.0 - Pool-aware scheduler support
        5.3.0 - Consistency group modification support
        6.0.0 - Over subscription support
                Create consistency group from cgsnapshot support
                Multiple pools support enhancement
                Manage/unmanage volume revise
                White list target ports support
                Snap copy support
                Support efficient non-disruptive backup
        7.0.0 - Clone consistency group support
    """

    def __init__(self, *args, **kwargs):

        super(EMCCLIISCSIDriver, self).__init__(*args, **kwargs)
        self.cli = emc_vnx_cli.getEMCVnxCli(
            'iSCSI',
            configuration=self.configuration)
        self.VERSION = self.cli.VERSION

    def check_for_setup_error(self):
        pass

    def create_volume(self, volume):
        """Creates a VNX volume."""
        return self.cli.create_volume(volume)

    def create_volume_from_snapshot(self, volume, snapshot):
        """Creates a volume from a snapshot."""
        return self.cli.create_volume_from_snapshot(volume, snapshot)

    def create_cloned_volume(self, volume, src_vref):
        """Creates a cloned volume."""
        return self.cli.create_cloned_volume(volume, src_vref)

    def extend_volume(self, volume, new_size):
        """Extend a volume."""
        self.cli.extend_volume(volume, new_size)

    def delete_volume(self, volume):
        """Deletes a VNX volume."""
        self.cli.delete_volume(volume)

    def migrate_volume(self, ctxt, volume, host):
        return self.cli.migrate_volume(ctxt, volume, host)

    def retype(self, ctxt, volume, new_type, diff, host):
        """Convert the volume to be of the new type."""
        return self.cli.retype(ctxt, volume, new_type, diff, host)

    def create_snapshot(self, snapshot):
        """Creates a snapshot."""
        self.cli.create_snapshot(snapshot)

    def delete_snapshot(self, snapshot):
        """Deletes a snapshot."""
        self.cli.delete_snapshot(snapshot)

    def ensure_export(self, context, volume):
        """Driver entry point to get the export info for an existing volume."""
        pass

    def create_export(self, context, volume, connector):
        """Driver entry point to get the export info for a new volume."""
        pass

    def remove_export(self, context, volume):
        """Driver entry point to remove an export for a volume."""
        pass

    def check_for_export(self, context, volume_id):
        """Make sure volume is exported."""
        pass

    def initialize_connection(self, volume, connector):
        """Initializes the connection and returns connection info.

        The iscsi driver returns a driver_volume_type of 'iscsi'.
        the format of the driver data is defined in vnx_get_iscsi_properties.
        Example return value (multipath is not enabled)::

            {
                'driver_volume_type': 'iscsi'
                'data': {
                    'target_discovered': True,
                    'target_iqn': 'iqn.2010-10.org.openstack:volume-00000001',
                    'target_portal': '127.0.0.0.1:3260',
                    'target_lun': 1,
                    'access_mode': 'rw'
                }
            }

        Example return value (multipath is enabled)::

            {
                'driver_volume_type': 'iscsi'
                'data': {
                    'target_discovered': True,
                    'target_iqns': ['iqn.2010-10.org.openstack:volume-00001',
                                    'iqn.2010-10.org.openstack:volume-00002'],
                    'target_portals': ['127.0.0.1:3260', '127.0.1.1:3260'],
                    'target_luns': [1, 1],
                    'access_mode': 'rw'
                }
            }

        """
        return self.cli.initialize_connection(volume, connector)

    def terminate_connection(self, volume, connector, **kwargs):
        """Disallow connection from connector."""
        self.cli.terminate_connection(volume, connector)

    def get_volume_stats(self, refresh=False):
        """Get volume status.

        If 'refresh' is True, run update the stats first.
        """
        if refresh:
            self.update_volume_stats()

        return self._stats

    def update_volume_stats(self):
        """Retrieve status info from volume group."""
        LOG.debug("Updating volume status.")
        # retrieving the volume update from the VNX
        data = self.cli.update_volume_stats()

        backend_name = self.configuration.safe_get('volume_backend_name')
        data['volume_backend_name'] = backend_name or 'EMCCLIISCSIDriver'
        data['storage_protocol'] = 'iSCSI'

        self._stats = data

    def manage_existing(self, volume, existing_ref):
        """Manage an existing lun in the array.

        The lun should be in a manageable pool backend, otherwise
        error would return.
        Rename the backend storage object so that it matches the,
        volume['name'] which is how drivers traditionally map between a
        cinder volume and the associated backend storage object.

        manage_existing_ref:{
            'source-id':<lun id in VNX>
        }
        or
        manage_existing_ref:{
            'source-name':<lun name in VNX>
        }
        """
        return self.cli.manage_existing(volume, existing_ref)

    def manage_existing_get_size(self, volume, existing_ref):
        """Return size of volume to be managed by manage_existing."""
        return self.cli.manage_existing_get_size(volume, existing_ref)

    def create_consistencygroup(self, context, group):
        """Creates a consistencygroup."""
        return self.cli.create_consistencygroup(context, group)

    def delete_consistencygroup(self, context, group, volumes):
        """Deletes a consistency group."""
        return self.cli.delete_consistencygroup(
            context, group, volumes)

    def create_cgsnapshot(self, context, cgsnapshot, snapshots):
        """Creates a cgsnapshot."""
        return self.cli.create_cgsnapshot(
            context, cgsnapshot, snapshots)

    def delete_cgsnapshot(self, context, cgsnapshot, snapshots):
        """Deletes a cgsnapshot."""
        return self.cli.delete_cgsnapshot(
            context, cgsnapshot, snapshots)

    def get_pool(self, volume):
        """Returns the pool name of a volume."""
        return self.cli.get_pool(volume)

    def update_consistencygroup(self, context, group,
                                add_volumes,
                                remove_volumes):
        """Updates LUNs in consistency group."""
        return self.cli.update_consistencygroup(context, group,
                                                add_volumes,
                                                remove_volumes)

    def unmanage(self, volume):
        """Unmanages a volume."""
        self.cli.unmanage(volume)

    def create_consistencygroup_from_src(self, context, group, volumes,
                                         cgsnapshot=None, snapshots=None,
                                         source_cg=None, source_vols=None):
        """Creates a consistency group from source."""
        return self.cli.create_consistencygroup_from_src(context,
                                                         group,
                                                         volumes,
                                                         cgsnapshot,
                                                         snapshots,
                                                         source_cg,
                                                         source_vols)

    def update_migrated_volume(self, context, volume, new_volume,
                               original_volume_status=None):
        """Returns model update for migrated volume."""
        return self.cli.update_migrated_volume(context, volume, new_volume,
                                               original_volume_status)

    def create_export_snapshot(self, context, snapshot, connector):
        """Creates a snapshot mount point for snapshot."""
        return self.cli.create_export_snapshot(context, snapshot, connector)

    def remove_export_snapshot(self, context, snapshot):
        """Removes snapshot mount point for snapshot."""
        return self.cli.remove_export_snapshot(context, snapshot)

    def initialize_connection_snapshot(self, snapshot, connector, **kwargs):
        """Allows connection to snapshot."""
        return self.cli.initialize_connection_snapshot(snapshot,
                                                       connector,
                                                       **kwargs)

    def terminate_connection_snapshot(self, snapshot, connector, **kwargs):
        """Disallows connection to snapshot."""
        return self.cli.terminate_connection_snapshot(snapshot,
                                                      connector,
                                                      **kwargs)

    def backup_use_temp_snapshot(self):
        return True
